To a certain extent, I think there is truth both ways. There is a huge amount of opportunity, but it's a bit like developer training: badly needed, but basically impossible to scale effectively. What you really want are agents, rather than recruiters, really. Developers change jobs every few years and are always on the look out for either better or newer opportunities. Having an agent that is skilled at assessing those opportunities, good at negotiation and good at matching opportunities to a list of clients would be amazing. But you can't hire 20-40 sales people and bang random people off the internet into jobs at scale. It's an opportunity for an individual, or a small team, not for a VC.

And, yes. Boy would I like an agent to negotiate my next raise and find me a better job if my current employer says no....